Part YII] Beeson : Life History of Toon Borer. 9 
unarmed. Mandibles (fig. 3) pentadentate, the 3 upper teeth pointed, 
the 2 lower blunt. Labrum (fig. 6) with median incision , narrow, 
acute, the six setae L 1} L 2 , L g and M ls M 2 , M g arranged as in figure; 
labral punctures mesad of and closely approximate to the bases of 
setae M 2 . Maxillae, (fig. 4) Lacinia-galea with 4 long papillae, 2 lamin¬ 
ate, bifid and 2 cylindrical with a minute distal joint, also 3 short 
processes between the bases of the papillae ; third joint of maxillary 
palp with numerous short papillae. Spinneret (fig. 4) relatively short. 
Arrangement of setae on head of mature larva of 
llypsipyla robusta, Moore. 
Arrangement of Body Setce [see Plate I, fig. 3]. The homology of 
the setae as presented in the figure is tentative ; the relative lengths of 
the long and short setae are slightly exaggerated. 
Thorax. Pronotal Plate with 6 setae ; la, lb, Ic in a line, submar¬ 
ginal ; Ila dorso-caudad and lib caudad of la ; lie caudad of Ic, 
submarginal; lb, Ic, lie equidistant; III absent; IV and V on one shield ; 
VI bisetose. 
Mesothorax and metathorax with I, II, IV, and VI in a line and 
with III caudad of the line ; VI unisetose. 
Abdomen. Segments 1-6 with II ventrocaudad of I; III sub- 
spiracular I, III, IV, V and VII in a line with the spiracle; VII trisetose. 
Segment 7 similar but with V and VII not in a line, and VII bisetose. 
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